Priming charge.



' harmful acid residue of the explosion of the 3 UNITED STATES PATENT OFFICE.

WILLIAM H. BUELL, OF NEW HAVEN, CONNECTICUT, ASSIGNOR TO WINCHESTER REPEATING ARMS COMPANY, OF NEW HAVEN, CONNECTICUT, A CORPORATION OF CONNECTICUT.

PRIMING CHARGE.

Patented Mar. '7, 1916.

No Drawing. Original application filed October 21, 1913, Serial No. 796,441. Divided and this application filed June 18, 1914.

To all whom it may concern:

Be it known that L'WILLIAM H. BUELL, a citizen of the United States, residing 'at New Haven, in the county of New Haven, State of Connecticut, have invented a new and useful Improvement in Priming Charges,

especial utility in igniting the "various smokeless and black powders when used in center fire and rim. fire ammunition.

The purpose of my invention is to produce a priming charge which is particularly suited for use "with powders as now employed in firearms, and particularly small 'arms, such charge producing an explosion of not too greatlocal pressure, andbf sufficient heat, and leaving substantially no harmful residues; my invention further contemplates the modification of the flash of the priming charge, giving it greater length, and contemplates also the creation of an alkaline,

residue, which measurably neutralizes the powder, particularly of smokeless powder.

According to my invention I produce a priming charge by mixing intimately a detonating salt of hydrazoic acid with a, suitable nitrated organic body. For instance, I may add 3 parts by weight of nitrocellulose (preferably high nitrogen insoluble) to 1 part of lead hydrazoate, and mix the same to produce a substantially homogeneousproduct. While the detonating, salts of hydrazoic acid are too brisant for use alone in firearms, andespecially in small arms, the

, mixture above described will be found suitable for such use, the local pressure of the of the shell. 7

Serial No. 845,875.

In place of the nitro cellulose I may employ some other suitable nitrated organic body such for mstance, as nitrated starch,

-. the aromatic nitro compounds as trinitrotoluene; the nitro derivatives for carbamid or ureaas nitro urea; the aromatic diazo salts as diazo benzene nitrate; and the aromatic dlazo amido compounds as diazo amido benzene. While the proportions most suitable for the mixture may differ with various substancesand' also with various powders in connectlon with which the mixture is to be used, they are easily determined by anyone skilled in the art. I desire it to be understood that it is possible that some nitrated organic bodies, in combination with a detonating salt of hydrazoic acid, may not produce a primer having the explosive qualities above described, and that I therefore include in my invention the use of such bodies only as will in such combination producesuch a primer. 1

It is also to be understood that the term detonating salt o-f hydrazoic acid as used in the art, and by me int'his specification, refers only 't'oa salt of the heavy metals, and does not include salts of the alkali metals, although such salts may have slight detonating properties under certain abnormal conditions. 1 I

My invention further contemplates the presence of a third substance for the purpose of leaving an alkaline residue suited to.

neutralize wholly or measurably the acid residue left by the burning of the powder, particularly of smokeless powder, and also any acid residue which might be left from the I explosion of the, other ingredients of the primer. This substance is a salt or other compound which either is not affected by v the explosion or is broken up by the explosion, and in either case leaves the residue suitable for the purposes indicated. I may use sodium or potassium carbonate, barium nitrate, or potassium nitrate. I prefer, however, to use an alkali metal salt of hydrazoic acid, or an alkaline earth metal salt, or a double alkali metal and other metal salt, of such acid; such as for instance, the' sodium salt, or the potash salt, or the potassium c0- balt salt of such acid. The use of these last mentioned substances has the further great advantage of producing an increased flash, in addition to causing the residue of the exfor instance mix 6 collodion.

plosion of the primer to be alkaline.

parts by Weight of lead hydrazoate and 11 parts of nitro cellulose (preferably the high nitrogen insoluble) With 3 parts of sodium hydrazoate. It Will befound that thismixture when exploded,

will have all the advantages above claimed .for the mixture of the lead salt and nitro cellulose alone, and Will have the additional advantages of an increased flame, and of a beneficial alkaline residue. The proportions may have to be varied under different circumstances and conditions, and with different materials and for different powders, but they can readily be ascertained by anyone skilled in the art. It is possible that some compounds which upon ignition leave an alkaline residue and particularly some members of the roup of alkali metal, alkaline earth metal, and double alkali metal and metal salts of hydrazoic acid, may not operate as described in the combinations indi-) cated, and, if so, they are not included in my invention. In my mentioned salts of hydrazoic acidunder the general term of alkali metal salts of hydrazoic acid.

The mixtures above specifically referred to, either of two substances, or of three substances, constitute a fine White or light colored mass Which may be moistened with a gum solution and then introduced into the primer cups, Where it is seated under heavy pressure, and may then, if desired, be covered with paper or foil, or by a thin film of An anvil of any suitable construction may then be inserted into the cups. When the primer-is to be usedin'rim fire ammunition it is preferably given the treatmentwith the gum solution and then driven into the annular rim of the cartridge shell by centrifugal force. It may then be covered by collodion.

I have found that I may increase the sen-c sitiveness of themixture to a high degree,

by first mixing-the nitrated organic body, as.

for instance the nitrocellulose, with the alkaline residue producing salt, for instance the sodium hydrazoate, treating the mixture With amylacetate or other suitable solvent, in sufficient amount to obtain the proper consistency, permitting the mixture thus treated to harden and then grinding the same, and then adding to the ground sub stance the detonating salt, as lead hydrazoate. Glassmay be added at the same time with the detonating salt. .By this operation I obtain a primer in'which the alkaline residue producing salt is more intimately mixed With the nitrated organic for instance,

body than would be the case if all three ingradients Were simultaneously mixed in a dry state, and the sensltiveness of the mixture is thereby greatly increased. I obtain moreover a further useful result, namely Imay claims I group the above that the particles of the alkaline residue producing salt are surrounded by a film or covering of the nitrated body, so that such-parin character and of the proper igniting qual-. ity, so thatv a hot and uniform flame is pro-' duced Without excess of local pressure and With a minimum 'of harmful residue or none at all. The flame produced-has the proper velocity and intensity to ignitethe poyvder charge before imparting any appreciable motion to it before ignition, and thus effects an explosion having the maximum pressure.

near the breech of the gun, and not one Which. is delayed until the charge nears the muzzle, the portion of the barrel least adapted to Withstand bursting pressure.

- WVhile I may add other substances to my priming mixture, I prefer not to do 80. Thus, chlorate of potash, or some other oxi dizing compound, such as the perchlorates, nitrates and peroxids of barium, potassium, etc., may be added to the mixture, .or in part substituted for certain ingredients, but their presence is usually undesirable owing-to the production of increased local pressure.

I have also found that a mixture of a detonating salt of hydrazoic acid and an alkali metal salt of such acid forms a priming charge adapted for use in firearms. Such charge may be composed for example, of 45 4 parts by Weight of lead hydrazoa-te and '55 parts by WQl htOf sodium hydrazoate. In such a chargethe brisant effect of the lead salt is toned to a suflicient extent and a maximum value is obtained with regard to alkaline residue.

may also be mixed with a suitable non-gaseous fuel and a suitable oxidizing compound ple, 35 parts of sodium hydrazoate, 35 parts of antimony sulfid and 30 parts of potassium chlorate. In such a charge the alkali metal salt has for its principal purpose to neutralize measurably the injurious acid J residue formed by the reaction between the other ingredients of the charge. The alkali metal hydrazoate, as used in my invention, isof particular value because it is itself explosive and therefore adds this value to the charge in addition to its value in leaving an alkaline residue. a

I claim: a

' 1. 'A priming charge containing a mixture of a detonating salt of hydrazoic acid, anitrated organic body and a compound Which upon ignition Will leave an alkaline residue,

The alkali metal salt of hydrazoic acid substantially as and for the purpose 7 described.

2. A priming charge containing a mix- I ture of a detonating salt of hydrazoic acid,

ainitrated organic body and an alkali salt of hydrazoic acid, substantially as and for the purpose described.

3. A priming charge containing a mixture of a detonating salt of hydrazoic acid, nitro cellulose and an alkali salt of hydrazoic acid, substantially as and for the purpose described.

4. A priming charge containing a mixture of lead hydrazoate, a nitrated organic body and an alkali salt ofhydrazoic acid,

substantially as and for the purpose de- 8. A priming charge containing a mix-- ture of a detonating salt of hydrazoic acid and a finely divided substance the particles of which contain nitro cellulose and an alkali salt of hydrazoic acid, substantially as and for the purpose described.

9. A priming charge containing a mixture of a detonating salt of hydrazoic acid and a finely divided substance" the particles of which contain nitro cellulose and sodium hydrazoate, substantially as and for the purpose described.

10. A priming charge containing a mixture of lead hydrazoate and a finely divided substance the particles of which contain nitro cellulose and sodiumhydrazoate, substantially as and for the purpose described.

11. A priming charge containing a mixture of a detonating salt of hydrazoic acid and an alkali salt of said acid, substantially as and for the purpose described.

12. A priming charge containing a mixture of a detonating salt of hydrazoic acid and sodium hydrazoate, substantially as and for the purpose described.

13. A priming charge containing a mixture of lead hydrazoate and sodium hydrazoate, substantiallyas and for the purpose described.

In testimony whereof I have hereunto set my hand in the presence of'two subscribing witnesses.

WILLIAM H. BUELL.

Witnesses:

Fm'rz v. BRmsEN, JOHN A. FERGUSON. 

